* I have a feature which has a dependency to page_title.
* I am writing a DrupalWebTestCase which uses the feature.
* I get an ajax error of node_page_title_alter() already having been defined, when I try to run the test.
* The error goes away if I change line 658 in page_title.module to:include_once DRUPAL_ROOT . "/{$info['path']}/{$module}.page_title.inc";

* I also tested and the error goes away if I rely on the standard static var; which leads me to think there is a problem with drupal_static() OR it is getting reset somewhere in the module, during the test process.static $runonce = FALSE;

So my conclusion is that something in the test scenario is reseting the static $runonce. Hopefully this report can be of some help.